Evening star. [volume] (Washington, D.C.) 1854-1972, 1887-05-05


THE AIR AND THE SUMS OWN ATNosPHERR-rHI
RRsuLTs-OF THE MOUNT WHITNEY EXPEDITION.
The people OF this world have never seen the
sun as 1t really Is in their lives. This
was statement which Prof. s. P. Langley made
at the out OF his lecture at the National Museum
last evening on sunlight and the Earths Atmos-
phere." Notwithstanding the horse races, the
circus, and the oppressive heat, there were
enough people interested in Prof. Langley and
the sun to make q fair audience in the lecture
room. Prof. Langley, who spoke huently, illus
trated his meaning as he went along with com.
parsons that the most unScientific of his hearers
could comprehend. At the rear OF the platform a
large screen was suspended, and StereOptcOn views
and diagrams were throw q upon this Prot. Langley
referred TO PlatoS remarks about the wonder Of
man who had spent his life In a cave, upon be
atmosphere tthe speaker lkened to the roof Of
cave. 1t Is a reddish veil that holds back the
blue light OF the sun.
FROM THR BOTTOM OF THE OCEAN.
The Albatross in its deep sea dredging has
brought up fishes with enormous eyes, that tell OF
the faintness OF the light that filters down to their
depths. Such fish might regard the dim, green.
lsh light OF Its heaven as the full spendor OF the
sun, Win as much reason as we could regard the
sun we see as the sun as It really is We our.
selves are living at the bottom OF a great aerial
ocean, whose pillows roll hundreds OF miles over
our neads The white light we see is only the
depths. The lecture explained at some length
the meaning OF Selecuiye absorption OF the atmoS-
phere, showing how some OF the rays or colors Of
the spectrum are held back by the atmosphere.
me sun, too, like the earth, has its atmosphere,
which alters Its color. The presence OF the solar
atmosphere could be detected in observations OF
the sun by the darkening towards the edges.
the center OF the sun appeared Of light blue tint
and toward the edge swas red, approaching garnet
The professor showed On the screen a view OF the
suns corona remarking that the light received
from the sun had to come through this corona
also, as well as the suns atmosphere. He showed
also the wonderful tntricacy and beauty OF the
sun spots, with their plumes curling like cirrus
clouds, in the great winds that swept over the
surface OF the sun. One of these plumeS, two or
three times the size Of the continent OF North
America, lasted about fifteen minutes, and then
peared the color Of glowing red hydrogen-a beau
tlfui rose color-and through this they saw the
sun.
WHAT rs BER7sD IT7
The question was what was behind that. With
diagrams. Professor Langley explained simply
how observations had been taken of the sun when
in the zenith and when declining In the afternoon
so that In some cases the line OF vision Slanted
through the atmosphere, and In others went
through In the most direct way. The observations
that had been taken constantly for two years and
the delicate tests and measurements made il Ger
tain that the sun behind its atmosphere was blue
that is the cOlors OF the blue end OF the spectrum
were predominant.
THE COLOR OF THE Sun,
he said was very near that which the ladies knew
as lavender. When the light OF the sun came
slant1ng through the atmosphere the light was
diminished and the blue was cut out. The less
air that fntervened the more blue the sun looked.
The effect OF the atmospheric veil was to give the
sun an orange tint. The higher the sun was in
the sky the 6luer it looked Prot. Langley ex-
searches made at Allegheny City, explaining the
principles OF the bolometer, or ray-measurer, a
kind Of thermometer, so delicate that it can
Onp-hllndfod fhOlS3 n a
and indicate one One-milltonth. It depended on
The fact that the electric current will run faster
through a medium when the medium is warm
than when 1t Is not warm.
RISING 10 THE SURFACE.
Returning to the big-eyed fish at the bottom OF
the sea the lecturer spoke OF its getting more
correct view Of the sun by rising to the surface
It was possible for observers here to rise toward
baloon Climbing to the sop Of HEN h
that the expedition to the top q Mount Whitney,
made nearly 600 feet above the level OF the sea
Roughly speaking. this took them halfway to the
surface OF the aerial ocean. Though the atmoS-
denSer portion was near the earth, so that In go
ing miles up in the air one passed through
one-half At that height the blue end OF the
spectrum grew enormously.
WHAT WAS LEARNED AT MOUNT WHITNEY.
1t had been determined, he said, that only I'VE
per cent of the blue OF the was transmitted to
us through the suns atmosphere and the earth's
atmosphere. In other words, the blue Of the sun
was twenty times greater than 1t appeared to us,
while the red was only two times greater. One Oh the
results OF this Mount Whitney expedition had been
to show that the beat Of the sun beating upon the
earth would, annually, melt shell or Ice around
the earth 90 yards in thickness, instead OF 40
yards, as has been taught. Many points were
gained Of value to biologists in determining queS-
lions relating to the glacial age, and facts were
determined regarding the radiation Of heat from
the earth. ALI, he said, depended upon this curl
Gus Quasi-inteigent action rselective absorption.
These researches were not matter OF idle curl
osity, but something OF great value, even when re-
garded from narroweSt unitarian point OF view.
TO this Selective absorption this action going on
In the atmosphere, we owed our existence, and all
organic life depends upon 1t.